Question

我已经使用了几个小时，并且正在努力寻找解决方案。我创建了一个UIButton并添加了渐变背层。我要做的是在按钮上添加UIImage。我尝试使用setImage(image:, forState:)方法添加按钮。该图像显示在调试器的视图层次结构中，但不会出现在模拟器或iPad上。我还尝试添加自定义UIView并将其作为子视图添加到UIButton。我得到了相同的结果。有关如何在设备或模拟器上显示图像的任何想法？

deleteKey.frame = CGRect(x: 719, y: 10, width: 134.0, height: 63.0)
deleteKey.backgroundColor = UIColor.clearColor()

altGradients.append(CAGradientLayer())
altGradients[altGradients.count - 1].frame = CGRect(x: 0.0, y: 0.0, width: 134.0, height: 63.0)
altGradients[altGradients.count - 1].startPoint = CGPoint(x: 0.5, y: 0.0)
altGradients[altGradients.count - 1].endPoint = CGPoint(x: 0.5, y: 1.0)
altGradients[altGradients.count - 1].colors = altOffColor
altGradients[altGradients.count - 1].cornerRadius = 5.0

deleteKey.layer.addSublayer(altGradients[altGradients.count - 1])
deleteKey.adjustsImageWhenHighlighted = false
deleteKey.setImage(UIImage(named: "keyboard_delete.png")?.imageWithRenderingMode(.AlwaysOriginal), forState: .Normal)
deleteKey.addTarget(self, action: Selector("altKeyPressed:"), forControlEvents: .TouchDown)
deleteKey.addTarget(self, action: Selector("altKeyReleased:"), forControlEvents: .TouchUpInside)
altKeys.append(deleteKey)
self.addSubview(deleteKey)

Answer 1

为什么不在xcode中添加图像视图并使用所需的按钮图像，然后在其前面添加UI按钮并删除文本？这不需要任何编程，而且耗时少且复杂得多。

Answer 2

卢卡斯，我听从你的建议。我创建了一个UIImageView，并将其作为子视图添加到UIButton：

    // Delete key
    deleteKey.frame = CGRect(x: 719, y: 10, width: 134.0, height: 63.0)

    altGradients.append(CAGradientLayer())
    altGradients[altGradients.count - 1].frame = CGRect(x: 0.0, y: 0.0, width: 134.0, height: 63.0)
    altGradients[altGradients.count - 1].startPoint = CGPoint(x: 0.5, y: 0.0)
    altGradients[altGradients.count - 1].endPoint = CGPoint(x: 0.5, y: 1.0)
    altGradients[altGradients.count - 1].colors = altOffColor
    altGradients[altGradients.count - 1].cornerRadius = 5.0

    deleteKey.layer.addSublayer(altGradients[altGradients.count - 1])

    deleteImage.image = UIImage(named: "keyboard_delete.png")
    deleteImage.sizeToFit()
    deleteImage.center = CGPoint(x: deleteKey.frame.width / 2, y: deleteKey.frame.height / 2)

    deleteKey.addSubview(deleteImage)

    deleteKey.backgroundColor = UIColor.clearColor()
    deleteKey.addTarget(self, action: Selector("altKeyPressed:"), forControlEvents: .TouchDown)
    deleteKey.addTarget(self, action: Selector("altKeyReleased:"), forControlEvents: .TouchUpInside)
    altKeys.append(deleteKey)
    self.addSubview(deleteKey)

无法在Swift中的UIButton上显示图像

2 个答案: